Device for Authenticating Wanted NFC Interactions

ABSTRACT

An electronic device that includes a sensor module, a measuring module and a near field communication (NFC) device. The sensor module receives an input signal. The measuring module measures the strength of the input signal and determines whether the input meets a predefined threshold. If the strength of the input signal meets the predefined threshold, the measuring module activates the NFC device. If the strength of the input signal does not meet the predefined threshold, the measuring module de-activates the NFC device.

BACKGROUND

1. Field of Invention

The invention relates to near field communication (NFC) devices, andmore specifically to enabling and disabling the NFC device to preventunauthorized use.

2. Related Art

Near field communication (NFC) devices are being integrated intocommunication devices, such as mobile devices to provide an example, tofacilitate the use of these communication devices in conducting dailytransactions. For example, instead of carrying numerous credit cards,the credit information provided by these credit cards could be storedonto an NFC device. The NFC device is simply tapped to a credit cardterminal to relay the credit information to it to complete atransaction. As another example, a ticket writing system, such as thoseused in bus and train terminals, may simply write ticket fareinformation onto the NFC device instead of providing a ticket to apassenger. The passenger simply taps the NFC device to a reader to ridethe bus or the train without the use of a paper ticket.

Generally, NFC requires that NFC devices are present within a relativelysmall distance from one another so that their corresponding magneticfields can exchange information. Typically, the first NFC devicetransmits or generates a magnetic field modulated with the information,such as the credit information or the ticket fare information. Thismagnetic field inductively couples the information onto a second NFCdevice that is proximate to the first NFC device. The second NFC devicemay respond to the first NFC device by inductively coupling itscorresponding information onto the first NFC device.

As NFC devices are being used to conduct daily transactions that includesensitive information, such as, for example, credit card or bank accountnumbers, user addresses, etc., there is a risk of the information beingstolen from the NFC device in a way that is transparent to the owner ofthe NFC device. The threat exists as the attacker need only be in aphysical proximity of the NFC device and need not physically touch orinteract with a victim or with the NFC device of the victim. Forexample, an attacker may execute an electronic pick pocket on a victimcarrying an NFC device in his pocket, a bag or a brief case. Theattacker could use the NFC device of a genuine owner to make contactlesspurchases at a legitimate vendor that is remote from the NFC device thatis under a control of the victim.

For instance, a first attacker may walk next to the victim carrying anNFC device in his pocket that acts as a “leech.” The first attacker usesthe “leech” NFC device to make contact with the NFC device of thevictim. At the same time, a second attacker may walk around with a“ghost” NFC device that detects a radio frequency (“RF”) signal andcommand data from a legitimate NFC device reader, at for example, an ATMor a credit card reader of a legitimate vendor. The “ghost” NFC devicereceives RF signal and command data from the legitimate vendor,re-modulates the command data and rebroadcasts the reader signal to the“leech” NFC device.

The “leech” NFC device receives the re-broadcasted signal and commanddata from the “ghost” NFC device, de-modulates and amplifies the signal,and becomes a copy of a legitimate reader in real-time. The “leech” NFCdevice may amplify the signal, using, for example, a large low frequency(“LF”) or high frequency (“HF”) coil to increase the range of therebroadcasted signal from, for example, two feet to one hundred feet ormore.

As the unsuspecting victim (the owner of the NFC device) carries his NFCdevice, the NFC tag of his NFC device responds to the “leech” NFC deviceas though the “leech” NFC device was a genuine tag reader. Once the“leech” receives the NFC tag signal from the NFC device of a victim, the“leech” de-modulates the signal and transmits the signal to the “ghost”NFC device. The “ghost” NFC device receives the signal from the “leech”device and uses the signal to load modulate its coil and respond to thelegitimate reader as though the “ghost” NFC device included an NFC tagof a legitimate NFC device of the owner.

Conventional systems attempt to prevent these types of electronicattacks by having the owner of the NFC device activate the NFC deviceprior to use. For example, the NFC device owner may be asked to turn onthe tag mode of the NFC device, using, for example, the phone menusystem on the communication device or opening the communication device.However, activating NFC device prior to executing a transaction may beburdensome on the consumer and degrade the consumer experience. Thus,there is a need for systems and methods that activate and deactivate theNFC device in a way that is seamless to the owner.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

Embodiments of the invention are described with reference to theaccompanying drawings. In the drawings, like reference numbers indicateidentical or functionally similar elements. Additionally, the left mostdigit(s) of a reference number identifies the drawing in which thereference number first appears.

FIG. 1 illustrates a block diagram of an NFC environment, according toan exemplary embodiment of the invention.

FIG. 2 illustrates a block diagram of an NFC device that is implementedas part of the NFC environment, according to an exemplary embodiment ofthe invention.

FIG. 3 illustrates a block diagram of an electronic device that includesa resonance device for activating an NFC device, according to anexemplary embodiment of the invention.

FIG. 4 illustrates a block diagram of an electronic device that includesa pressure sensor for activating an NFC device, according to anexemplary embodiment of the invention.

FIG. 5 illustrates a block diagram of an electronic device that includesan optical detector for activating an NFC device, according to anexemplary embodiment of the invention.

FIG. 6 illustrates a block diagram of an electronic device that includesa frequency detector for activating an NFC device, according to anexemplary embodiment of the invention.

FIG. 7 illustrates a block diagram of an electronic device that includesa conductive casing for activating an NFC device, according to anexemplary embodiment of the invention.

FIGS. 8A-B illustrate a block diagram of electronic device 800 thatincludes a conductive material on casings to activate an NFC device,according to an exemplary embodiment of the invention.

FIG. 9 is a flowchart of a method for activating an NFC device,according to an exemplary embodiment of the invention.

The invention will now be described with reference to the accompanyingdrawings. In the drawings, like reference numbers generally indicateidentical, functionally similar, and/or structurally similar elements.The drawing in which an element first appears is indicated by theleftmost digit(s) in the reference number.

DETAILED DESCRIPTION OF THE INVENTION

The following Detailed Description refers to accompanying drawings toillustrate exemplary embodiments consistent with the invention.References in the Detailed Description to “one exemplary embodiment,”“an exemplary embodiment,” “an example exemplary embodiment,” etc.,indicate that the exemplary embodiment described may include aparticular feature, structure, or characteristic, but every exemplaryembodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same exemplary embodiment. Further, when a particularfeature, structure, or characteristic is described in connection with anexemplary embodiment, it is within the knowledge of those skilled in therelevant art(s) to affect such feature, structure, or characteristic inconnection with other exemplary embodiments whether or not explicitlydescribed.

The exemplary embodiments described herein are provided for illustrativepurposes, and are not limiting. Other exemplary embodiments arepossible, and modifications may be made to the exemplary embodimentswithin the spirit and scope of the invention. Therefore, the DetailedDescription is not meant to limit the invention. Rather, the scope ofthe invention is defined only in accordance with the following claimsand their equivalents.

Embodiments of the invention may be implemented in hardware, firmware,software, or any combination thereof. Embodiments of the invention mayalso be implemented as instructions stored on a machine-readable medium,which may be read and executed by one or more processors. Amachine-readable medium may include any mechanism for storing ortransmitting information in a form readable by a machine (e.g., acomputing device). For example, a machine-readable medium may includeread only memory (ROM); random access memory (RAM); magnetic diskstorage media; optical storage media; flash memory devices; electrical,optical, acoustical or other forms of propagated signals (e.g., carrierwaves, infrared signals, digital signals, etc.), and others. Further,firmware, software, routines, instructions, etc. may be described hereinas performing certain actions. However, it should be appreciated thatsuch descriptions are merely for convenience and that such actions infact result from computing devices, processors, controllers, or otherdevices executing the firmware, software, routines, instructions, etc.

The following Detailed Description of the exemplary embodiments will sofully reveal the general nature of the invention that others can, byapplying knowledge of those skilled in relevant art(s), readily modifyand/or adapt for various applications such exemplary embodiments,without undue experimentation, without departing from the spirit andscope of the invention. Therefore, such adaptations and modificationsare intended to be within the meaning and plurality of equivalents ofthe exemplary embodiments based upon the teaching and guidance presentedherein. It is to be understood that the phraseology or terminologyherein is for the purpose of description and not of limitation, suchthat the terminology or phraseology of the present specification is tobe interpreted by those skilled in relevant art(s) in light of theteachings herein.

Although the description of the present invention is to be described interms of an NFC device, those skilled in the relevant art(s) willrecognize that the present invention may be applicable to othercommunications, such as radio-frequency identification (“RFID”) devices,that use the near field and/or far field without departing from thespirit and scope of the present invention. For example, although thepresent invention is to be described using NFC devices, those skilled inthe relevant art(s) will recognize that functions of these NFC devicesmay be applicable to other communications devices that use the nearfield and/or the far field without departing from the spirit and scopeof the present invention.

FIG. 1 illustrates a block diagram of an NFC environment 100 accordingto an exemplary embodiment of the invention. NFC environment 100provides wireless communication of information, such as one of commandsand/or data, among a first NFC device 102 and a second NFC device 104that are sufficiently proximate to each other. The first NFC device 102and/or the second NFC device 104 may be implemented as a standalone or adiscrete device or may be incorporated within or coupled to anotherelectrical device or host device such as a mobile telephone, a portablecomputing device, another computing device such as a personal, a laptop,or a desktop computer, a computer peripheral such as a printer, aportable audio and/or video player, a payment system, a ticket writingsystem such as a parking ticketing system, a bus ticketing system, atrain ticketing system or an entrance ticketing system to provide someexamples, or in a ticket reading system, a toy, a game, a poster,packaging, advertising material, a product inventory checking systemand/or any other suitable electronic device that will be apparent tothose skilled in the relevant art(s) without departing from the spiritand scope of the invention.

Conventionally, an operator may operate and/or control the first NFCdevice 102 and/or the second NFC device 104 using a user interface, suchas a touch-screen display, an alphanumeric keypad, a microphone, amouse, a speaker, any other suitable user interface that will beapparent to those skilled in the relevant art(s) without departing fromthe spirit and scope of the invention, or any combination thereof. Theuser interface may be configured to allow the operator to provideinformation, such as data and/or one or more commands to provide someexamples, to the first NFC device 102 and/or the second NFC device 104.Herein, information includes data that is to be transferred from a firstNFC-capable device to a second NFC-capable device, data that is to bestored or used by the first NFC-capable device and/or the secondNFC-capable device, data that is to be provided to the first NFC-capabledevice and/or the second NFC-capable device, data that is to be providedto an operator of the first NFC-capable device and/or the secondNFC-capable device, or any combination thereof. Herein, an NFC-capabledevice refers to an electrical device or host device that is integratedwith an NFC device or the NFC device itself.

The information may also include one or more commands to be executed bythe first NFC-capable device and/or the second NFC-capable device. Theuser interface may be configured to provide the information from thefirst NFC device 102 and/or the second NFC device 104 to the operator.

The first NFC device 102 and/or the second NFC device 104 interact witheach other to exchange the information in a peer-to-peer (P2P)communication mode or a reader/writer (R/W) communication mode. In theP2P communication mode, the first NFC device 102 and the second NFCdevice 104 may be configured to operate according to an activecommunication mode and/or a passive communication mode. The first NFCdevice 102 modulates its corresponding information onto a first carrierwave, referred to as a modulated information communication, andgenerates a first magnetic field by applying the modulated informationcommunication to the first antenna to provide a first informationcommunication 152. The first NFC device 102 ceases to generate the firstmagnetic field after transferring its corresponding information to thesecond NFC device 104 in the active communication mode. Alternatively,in the passive communication mode, the first NFC device 102 continues toapply the first carrier wave without its corresponding information,referred to as an unmodulated information communication, to continue toprovide the first information communication 152 once the information hasbeen transferred to the second NFC device 104.

The first NFC device 102 is sufficiently proximate to the second NFCdevice 104 such that the first information communication 152 isinductively coupled onto a second antenna of the second NFC device 104.The second NFC device 104 demodulates the first informationcommunication 152 to recover the information. The second NFC device 104may respond to the information by modulating its correspondinginformation onto a second carrier wave and generating a second magneticfield by applying this modulated information communication to the secondantenna to provide a second modulated information communication 154 inthe active communication mode. Alternatively, the second NFC device 104may respond to the information by modulating the second antenna with itscorresponding information to modulate the first carrier wave to providethe second modulated information communication 154 in the passivecommunication mode.

In the R/W communication mode, the first NFC device 102 is configured tooperate in an initiator, or reader, mode of operation and the second NFCdevice 104 is configured to operate in a target, or tag, mode ofoperation. However, this example is not limiting, those skilled in therelevant art(s) will recognize that the first NFC device 102 may beconfigured to operate in the tag mode and the second'NFC device 104 maybe configured to operate in the reader mode in accordance with theteachings herein, without departing from the spirit and scope of thepresent invention. The first NEC device 102 modulates its correspondinginformation onto the first carrier wave and generates the first magneticfield by applying the modulated information communication to the firstantenna to provide the first information communication 152. The firstNFC device 102 continues to apply the first carrier wave without itscorresponding information to continue to provide the first informationcommunication 152 once the information has been transferred to thesecond NFC device 104. The first NFC device 102 is sufficientlyproximate to the second NFC device 104 such that the first informationcommunication 152 is inductively coupled onto a second antenna of thesecond NFC device 104.

The second NFC device 104 derives or harvests power from the firstinformation communication 152 to recover, to process, and/or to providea response to the information. The second NFC device 104 demodulates thefirst information communication 152 to recover and/or to process theinformation. The second NFC device 104 may respond to the information bymodulating the second antenna with its corresponding information tomodulate the first carrier wave to provide the second modulatedinformation communication.

Further operations of the first NFC device 102 and/or the second NFCdevice 104 may be described in International Standard ISO/IE18092:2004(E), “Information Technology—Telecommunications andInformation Exchange Between Systems—Near Field Communication—Interfaceand Protocol (NFCIP-1),” published on Apr. 1, 2004 and InternationalStandard ISO/IE 21481:2005(E), “InformationTechnology—Telecommunications and Information Exchange BetweenSystems—Near Field Communication—Interface and Protocol-2 (NFCIP-2),”published on Jan. 15, 2005, each of which is incorporated by referenceherein in its entirety.

FIG. 2 illustrates a block diagram of a first NFC device that isimplemented as part of the NFC environment, according to an exemplaryembodiment of the invention. An NFC device 200 is configured to operatein a reader mode of operation to initiate an exchange of information,such as data and/or one or more commands to provide some examples, withother NFC devices. An NFC device 200 may also be is configured tooperate in a target, or tag, mode of operation to respond to a requestto exchange information, such as data and/or one or more commands toprovide some examples, with another NFC-capable device. NFC device 200may also be configured to operate in a communicator mode of operation toinitiate an exchange of information, such as data and/or one or morecommands to provide some examples, with other NFC-capable devices and torespond to a request to exchange the information from other NFC-capabledevices.

An operator may operate and/or control the NFC device 200 using a userinterface and/or may touch, or be sufficiently proximate to, an antennamodule of the NFC device 200. For example, the operator may provideinformation to the NFC device 200 by touching, or being sufficientlyproximate to, the antenna module. The NFC device 200 includes acontroller module 202, a modulator module 204, an antenna module 206, ademodulator module 208, and, optionally, a power harvesting module 268.The NFC device 200 may represent an exemplary embodiment of the firstNFC device 102 and/or the second NFC device 104.

The controller module 202 controls overall operation and/orconfiguration of the NFC device 200. The controller module 202 receivesinformation 250 from one or more data storage devices such as one ormore contactless transponders, one or more contactless tags, one or morecontactless smartcards, or any other machine-readable mediums that willbe apparent to those skilled in the relevant art(s) without departingfrom the spirit and scope of the invention, or any combination thereof.The other machine-readable medium may include, but is not limited to,read only memory (ROM), random access memory (RAM), magnetic diskstorage media, optical storage media, flash memory devices, electrical,optical, acoustical or other forms of propagated signals such as carrierwaves, infrared signals, digital signals to provide some examples. Thecontroller module 202 may also receive the information 250 from a userinterface such as a touch-screen display, an alphanumeric keypad, amicrophone, a mouse, a speaker, any other suitable user interface thatwill be apparent to those skilled in the relevant art(s) withoutdeparting from the spirit and scope of the invention to provide someexamples. The controller module 202 may further receive the information250 from other electrical devices or host devices coupled to the NFCdevice 200.

Typically, the controller module provides the information 250 astransmission information 252 for transmission to another NFC-capabledevice. However, the controller module 202 may also use the information250 to control the overall operation and/or configuration of the NFCdevice 200. For example, the controller module 202 may issue and/orexecute the one or more commands in accordance with the data, ifappropriate, to control operations of the NFC device 200, such as atransmission power, a transmission data rate, a transmission frequency,a modulation scheme, a bit and/or a byte encoding scheme and/or anyother suitable operation parameter that will be apparent to thoseskilled in the relevant art(s) without departing from the spirit andscope of the invention, of other NFC-capable devices.

Additionally, the controller module 202 may format the information 250into information frames and may perform error encoding, such as cyclicredundancy check (CRC) to provide an example, on the information framesto provide the transmission information 252. The information frames mayinclude frame delimiters to indicate a start and/or an end of each ofthe information frames. The controller module 202 may additionallyarrange multiple information frames to form sequences of informationframes to synchronize and/or to calibrate the NFC device 200 and/oranother NFC-capable device. The sequences may include sequencedelimiters to indicate a start and/or an end of each of the sequences.

The modulator module 204 modulates the transmission information 252 ontoa carrier wave, such as a radio frequency carrier wave having afrequency of approximately 13.56 MHz to provide an example, using anysuitable analog or digital modulation technique to provide a modulatedinformation communication as transmission information 254. The suitableanalog or digital modulation technique may include amplitude modulation(AM), frequency modulation (FM), phase modulation (PM), phase shiftkeying (PSK), frequency shift keying (FSK), amplitude shift keying(ASK), quadrature amplitude modulation (QAM) and/or any other suitablemodulation technique that will be apparent to those skilled in therelevant art(s). The modulator module 204 may continue to provide thecarrier wave to provide an unmodulated information communication as thetransmission information 254 once the transmission information 252 hasbeen transferred to another NFC-capable device. Alternatively, themodulator module 204 may cease to provide the transmission information254 once the transmission information 252 has been transferred toanother NFC-capable device

The antenna module 206 applies the transmission information 254 to aninductive coupling element, such as a resonant tuned circuit to providean example, to generate a magnetic field to provide a transmittedinformation communication 256. Additionally, another NFC-capable devicemay inductively couple a received communication signal 258 onto theinductive coupling element to provide a recovered communication signal260. For example, this other NFC-capable device may respond to theinformation by modulating its corresponding antenna with itscorresponding information to modulate the carrier wave to provide thereceived communication signal 258. As another example, this otherNFC-capable device may modulate its corresponding information onto itscorresponding carrier wave and generate its corresponding magnetic fieldby applying this modulated information communication to itscorresponding antenna to provide the received communication signal 258.

The demodulator module 208 demodulates the recovered communicationsignal 260 using any suitable analog or digital modulation technique toprovide reception information 262. The suitable analog or digitalde-modulation technique may include amplitude modulation (AM), frequencymodulation (FM), phase modulation (PM), phase shift keying (PSK),frequency shift keying (FSK), amplitude shift keying (ASK), quadratureamplitude modulation (QAM) and/or any other suitable modulationtechnique that will be apparent to those skilled in the relevant art(s).

Typically, the controller mode provides the reception information 262 asrecovered information 266 to the data store, the user interface, and/orother electrical devices or host devices. However, the controller module202 may also use the reception information 262 to control the overalloperation and/or configuration of the NFC device 200. The receptioninformation 262 may include one or more commands and/or data. Thecontroller module 202 may issue and/or execute the one or more commandsto control the overall operation and/or configuration of the NFC device200. For example, the controller module 202 may issue and/or execute theone or more commands in accordance with the data, if appropriate, tocontrol operations of the NFC device 200, such as a transmission power,a transmission data rate, a transmission frequency, a modulation scheme,a bit and/or a byte encoding scheme and/or any other suitable operationparameter that will be apparent to those skilled in the relevant art(s)without departing from the spirit and scope of the invention, of otherNFC-capable devices.

Additionally, the controller module 202 formats the receptioninformation 262 into a suitable format for transmission to the datastore, the user interface, and/or other electrical devices or hostdevices, and may perform error decoding, such as cyclic redundancy check(CRC) decoding to provide an example, on the reception information 262to provide recovered information 266.

Some NFC devices 200 may also include a power harvesting module 268. Thepower harvesting module 268 may harvest a power source from the receivedcommunication signal 258. The power source may include sufficient powerto adequately operate the controller module 202, the modulator module204, the antenna module 206, and/or the demodulator module 208.

Communication device that includes NFC device 200 may be an electronicdevice, such as a portable computing device under a control of a user.Example electronic devices may include, without limitation, personalcomputers, mobile communication devices, (e.g. smart phones, tabletcomputing devices, notebooks), etc. Electronic devices typically includea casing on some or all sides of the electronic device, to protect theNFC device, processor, memory, and other electronic components integralto the functionality of the electronic device.

In an embodiment, the one or more casings on the electronic device maybe configured to activate and deactivate the tag mode of NFC device 200.The casings may be configured to activate the tag mode functionality ofNFC device 200 and/or passive peer to peer mode functionality of NFCdevice 200 (although the examples below are described in terms of thetag mode functionality for the ease of understanding the invention) whena user is holding the electronic device in a way that is transparent tothe user. For example, when a user holds a device, a user may come intocontact with multiple casings. When the electronic device determinesthat a user comes into contact with multiple casing, the tag mode devicemay be activated. Similarly, when the electronic device determines thata user does not come into contact with any casings, or with a number ofcasings that is less than a predefined threshold, the tag mode on NFCdevice deactivates. This functionality prevents the user of theelectronic device becoming a victim to the electronic pick-pocketingdescribed above.

FIG. 3 illustrates a block diagram of an electronic device 300 thatincludes a resonance detector for activating an NFC device, according toan exemplary embodiment of the invention. Although the block diagramdescribed herein includes a single casing 302 of electronic device 300,a person skilled in the art will appreciate that electronic device mayinclude multiple casings that include the embodiments of the presentinvention. Casing 302 may be a casing made of a plastic material,metallic material, or other material known to a person skilled in therelevant art.

The side of casing 302 internal to electronic device 300 includes aresonance device 304. Resonance device 304 may include conductive ink. Aperson skilled in the art will appreciate that the conductive ink is amaterial that may be a fired high solids system or a polymer thick film(PTF) system. Conductive ink allows circuits to be drawn or printed on avariety of substrate materials that contain conductive materials, suchas, for example, powered or flaked silver, or carbon-like materials.

In another embodiment, resonance device 304 includes a printed circuitboard (“PCB”). A person skilled in the art will appreciate that a PCBconnects electronic components using conductive pathways, tracks orsignal traces etched from copper sheets laminated onto a non-conductivesubstrate. Example PCB boards may include a printed wiring board (PWB),etched wiring board, or a printed circuit board assembly (PCBA).

Resonance device includes an oscillating circuit 306. In an embodiment,oscillating circuit 306 may be printed on a conductive ink. In anotherembodiment, oscillating circuit 306 may be printed on the PCB board.

Example oscillating circuit 306 includes a capacitor 308, a resistor309, an inductor 310, and a voltage differential 312. A person skilledin the art will appreciate that this embodiment of oscillating circuit306 is not limiting, and other types of oscillating circuits may beused.

Oscillating circuit 306 uses capacitor 308 as a tuning element. When auser of electronic device 300 holds electronic device 300 with hishand(s), the proximity of the hand(s) adds a dielectric or apolarization component to capacitor 308. The dielectric or polarizationcomponent increases the capacitance of capacitor 308, and is indicativethat electronic device 300 is being held by the user, as opposed tobeing carried in a bag or a briefcase. When the user of electronicdevice 300 ends contact with electronic device 300, by for example,putting electronic device 300 into a bag or a briefcase, the capacitanceon capacitor 308 decreases.

A person skilled in the art will appreciate that an increase incapacitance is proportional to a decrease in a frequency of oscillatingcircuit 306. To measure the increase and decrease of the capacitance oncapacitor 308, oscillating circuit may be connected to a frequencydetection module 314.

Frequency detection module may be housed on NFC device 200 or onelectronic device 300. Example, frequency detection module 314 mayinclude an analog edge detector or a digital counting circuit. Frequencydetection module 314 may enable and disable the tag mode on NFC device200. For example, when a user holds electronic device 300, thecapacitance on capacitor 308 increases. This results in a decrease ofthe frequency of oscillating circuit 306. When frequency decreases belowa predefined threshold, frequency detection module may send a signal toNFC device 200 to activate the tag mode.

When the user completes using electronic device 300 and placeselectronic device back into a bag or a briefcase, the user no longertouches the casing and the capacitance across capacitor 308 decreases.The decrease of the capacitance is associated with an increase infrequency of oscillating circuit 306. When the frequency increases abovea predefined threshold, frequency detection module 314 sends a signal tocontroller 202 to disable the tag mode on NFC device 200, so that theNFC device 200 does not respond to an electronic attack.

In an embodiment, the decrease in frequency below a predefined thresholdon multiple casings is indicative that a device is being held. Forexample, when a user holds electronic device 300, the user may come intocontact with several casings 302 of electronic device 300. Thus, in anembodiment, a capacitance on a predetermined number of casings 302 mustincrease before the tag mode on NFC device 200 is activated. Similarly,when capacitance on a predetermined number of casings 302 falls below apredefined threshold, the tag mode on NFC device 200 deactivates.

FIG. 4 illustrates a block diagram of an electronic device 400 thatincludes a pressure sensor for activating an NFC device, according to anexemplary embodiment of the invention. Although, the block diagramdescribed herein includes a single casing 402, electronic device 400 mayinclude multiple casings 402.

The side of casing 402 internal to electronic device 400 includes apressure sensor 404. In an embodiment, pressure sensor 404 may belocated on one or more casings 402. Pressure sensor 404 measurespressure that is exerted on each casing 402.

Pressure sensor 404 may include quantum tunneling composites (QTCs). AQTC includes composite metals as conductive elements and anon-conducting elastomeric binder as an insulator. A person skilled inthe art will appreciate that a QTC utilizes quantum tunneling, where,when pressure is not applied to, the conductive elements are insulatedfrom each other by a non-conducting elastomeric binder as they are toofar apart to conduct electricity. When a user applies pressure to casing402, the conductive elements become closer and the electrons may tunnelthrough the insulator and carry the electric charge from one conductiveelement to the other. Once the electricity begins to pass from oneconductive metal to another, the resistance of the QTC increasesexponentially.

In an embodiment, NFC device 200 includes a resistance measuring module406. Resistance measuring module 406 measures resistance that a userapplies to casings 402 located on various sides of electronic device400. When a user of electronic device 400 is holding electronic device400, the user exerts pressure on one or more casings 402. Resistancemeasuring module 406 measures the resistance exerted on each casing 402,and when the resistance of one or more casings 402 increases above apredefined threshold, resistance measuring module 406 sends a signal tocontroller 202 of NFC device 200 to enable the tag mode.

Similarly, when resistance measuring module 406 determines that theresistance on one or more casings 402 falls below a predefinedthreshold, resistance measuring module 406 sends a signal to controller202 to disable the tag mode on NFC device 200.

In an embodiment, resistance measuring module 406 may detect an increasein resistance on multiple casing 402 that are parallel to each other.Enabling tag mode when resistance measuring module 406 determines anincrease in resistance on parallel casings 402 may avoid enabling thetag mode when electronic device 400 is laying on a table or in a bottomof a bag and has pressure exerted on a single casing 402.

FIG. 5 illustrates a block diagram of an electronic device 500 thatincludes a photodetector for activating an NFC device, according to anexemplary embodiment of the invention. As in the previous embodiments,the block diagram described herein includes a single casing 502.However, electronic device 500 may include multiple casings 502.

The side of casing 502 internal to electronic device 500 includes alight source 504. Light sources 504 may be located on one or morecasings 502 of electronic device 500. In an embodiment, casings 502allow light source 504 to emit light outside of electronic device 500,through, for example, a transparent casing 502 or an opening in thecasing that may be carved out for light source 504. Light source 504 maybe any light producing source, such as, without limitation, a laser, aninfra-red LED, or another source known to a person skilled in the artthat emits light. In an embodiment, the light source 504 emits lightsuch that the user is not aware that the light is being emitted.

In an embodiment, electronic device 500 or NFC device 200 included onelectronic device 500 includes a photodetector 506. Photodetector 506 isa device that senses light or other electromagnetic energy associatedwith light or light intensity. Example, photodetector 506 may be aphotodiode or an amplifier circuit that detects, for example, aninfra-red light, laser light, changes in light intensity, etc.

When light source 504 emits light through casing 502, the fiat may bereflected at a certain rate. For example, the farther the object thatreflects the light emitted from light source 504, the more time it takesfor the light to reflect and travel back to electronic device 500. Whena user is holding electronic device 500 the rate of reflection isaffected by the proximity of a hand of a user to electronic device 500.

Photodetector 506 determines the rate of reflection of the light whenlight sources 504 emits the light and the light reflects from the handof a user. When a rate of reflection meets a predefined threshold,photodetector 506 sends a signal to controller 202 to activate tag modeon NFC device 200. Similarly, when a user places electronic device 500in a bag, the rate of reflection decreases and photodetector 506 sends asignal to controller 202 to disable the tag mode on NFC device 200.

In an embodiment, the photodetector 506 may determine the rate ofreflection from the light sources 504 that emit light from multiplecasings 502. For example, when a user holds electronic device 500, theuser may come into contact with several casings 502 of electronic device500. Thus, in an embodiment, a rate of reflection from a predeterminednumber of casings 502 must meet a predetermined threshold before NFCdevice 200 may be activated. Similarly, when a rate of reflection meetsa predefined threshold on a fewer casings 502 then a predeterminednumber of casing 502, tag mode on NFC device 200 may deactivate.

In another embodiment, photodetector 506 may detect ambient light thatelectronic device 500 may receive through an opening in multiple casings502. In this embodiment, light source 504 may not be present inelectronic device 500 or may not be turned on. When photodetector 506detects ambient light from an opening in multiple casings 502 that isabove a predefined threshold, photodetector 506 sends a signal tocontroller 202 to activate tag mode on NFC device 200. A person skilledin the art will appreciate that photodetector 506 may receive ambientlight when a user retrieves electronic device 500 from a bag, a briefcase, or from a desk.

In another embodiment photodetector 506 may detect when electronicdevice 500 receives little or no light. For example, when electronicdevice 500 is in a bag or inside a drawer of a desk, the openings inmultiple casing 502 may receive little to no light. When the amount ofdetected light falls below a predefined threshold, photodetector 506sends a signal to controller 202 that disables the tag mode on NFCdevice 200.

FIG. 6 illustrates a block diagram of an electronic device 600 thatincludes a frequency detection module for activating an NFC device,according to an exemplary embodiment of the invention.

NFC device 200 may also be housed on an electronic device 600 thatincludes a frequency detection module 604 that is communicativelycoupled to antenna module 206 described herein.

Frequency detection module 604 measures the changes in tuned frequencythat is emitted by antenna module 206. For example, when a user touchesthe antenna or components of the antenna on electronic device 600,antenna module 206 causes a change in an at least one characteristicimpedance of at least one antenna component. The changes incharacteristic impedance reflect the change in a frequency of theantenna associated with NFC device 200.

Frequency detection module 604 measures the change in frequency responseof the antenna. When frequency detection module 604 determines that achange in frequency response is greater than the predefined threshold,frequency detection module 604 sends a signal to controller 202 toactivate the tag mode on NFC device 200. Similarly, when a usercompletes using electronic device 600 and does not touch the antenna onelectronic device 600, the frequency response falls below a predefinedthreshold and frequency detection module 604 sends a signal tocontroller 202 to disable the tag mode on NFC device 200.

FIG. 7 illustrates a block diagram of an electronic device 700 thatincludes a conductive casing to activate an NFC device, according to anexemplary embodiment of the invention. As in the previous embodiments,the block diagram described herein includes a single casing 702,electronic device 700 may include multiple casings 702.

The outside surface of casing 702 may include a conductive surface 704.Conductive surface 704 may, for example, become conductive whenelectronic device 700 is picked up by a user.

Casing 702 that includes conductive surface 704 may be connected to areceiver frequency (RF) circuit 706. In an embodiment, RF circuit may beincluded on NEC device 200 or electronic device 700. A person skilled inthe art will appreciate that RF circuit 706 is an electronic circuitthat receives and processes a frequency signal from an antenna. ExampleRF circuit 706 may be a radio frequency circuit that may be configuredto receive FM band radio or a mains hum of approximately 50 Hz.

When a user holds electronic device 700 and comes into contact withconductive surface 704, the body of the user acts as an antenna. Thebody acting as an antenna increases the frequency signal emitted byelectronic device 700 and detected by RF circuit 706.

When the frequency signal detected by RF circuit 706 increases above apredefined threshold, RF circuit 706 sends a signal to controller 202 toactivate the tag mode on NFC device 200. Similarly, when a usercompletes using electronic device 700 and places electronic device 700into a bag or a pocket, the frequency decreases below a predefinedthreshold. When RF circuit 706 detects a decrease in frequency, RFcircuit 706 sends a signal to controller 202 to disable the tag mode onNFC device 200.

FIGS. 8A-B illustrate a block diagram of an electronic device 800 (e.g.,a cell phone) that includes a conductive material on casings to activatean NFC device, according to an exemplary embodiment of the invention.FIG. 8A is an embodiment of a mobile device 800 that includes a frontcasing 802A and a back casing 802B. This is a so called clamshell case.However, the invention is not so limited, and any configuration of anelectronic device is contemplated. The external surface of front casing802A and back casing 802B includes a conductive material 804. Exampleconductive material 804 on casings 802A and 802B may be carbon loadedplastic strip. In an embodiment, insulated material 806 surroundsconductive material 804 on each casing 802A and 802B. Although, FIG. 8Adisplays a casing 802A, a person skilled in the relevant art willappreciate that casing 802B may include similar features. A personskilled in the art may also appreciate that conductive material 804 maybe included on other casings of electronic device 800. For example, anelectronic device could have two more conductive elements, which areinsulated from each other, on opposite sides of the device. In oneembodiment, the conductive elements are parallel to one another.

FIG. 8B illustrates components of an electronic device 800 that includesa conductive casing to activate an NFC device, according to an exemplaryembodiment of the invention. For example, conductive material 804 oncasings 802A and 802B may be connected to a device that measuresresistance, such as an ohmmeter 808. In an embodiment, ohmmeter 808 maybe included on NFC device 200 or electronic device 800. Becauseinsulating material 806 surrounds conductive material 804 on casings802A and 802B ohmmeter 808 may measure resistance of several mega ohmsbetween casings 802A and 802B.

When a user holds electronic device 800, a user touches conductivematerial 804 on casing 802A and 802B simultaneously. This causes ashorting of insulating material 806 of casings 802A and 802B, and acurrent flow between conductive materials 804 on casings 802A and 802Bthrough the body of a user.

Because, when a user holds electronic device 800 the current begins toflow between casings 802A and 802B, the resistance between casings 802Aand 802B drops, such that ohmmeter 808 may measure resistance of 20 k to100 k ohms. When ohmmeter 808 detects a decrease in resistance betweenconductive materials 804 on casings 802A and 802B that is below apredefined threshold, ohmmeter 808 sends a signal to controller 202 toactivate the tag mode on NFC device 200.

Similarly, when a user completes using electronic device 800 and placeselectronic device 800 into a bag or a pocket, the resistance betweenconductive material 804 on casings 802A and 802B increases. For example,the user no longer serves as a conductor between conductive material 804on casings 802A and 802B, which is surrounded by insulating material806. When ohmmeter 808 detects an increase in resistance that is above apredefined threshold, ohmmeter 808 sends a signal to controller 202 todisable the tag mode on NFC device 200.

FIG. 9 is a flowchart of a method 900 for activating an NFC device,according to an exemplary embodiment of the invention.

At step 902, an input signal is received. For example, electronicdevices 300-800 receive an input signal that may cause controller 202 toactivate the tag mode on NFC device 200. For example, resonance detector304 may receive electronic current, pressure sensor 404 may receive apressure input, photodetector 506 may receive a light input, frequencydetection module 604 may receive a frequency input, and RF circuit 706may receive a frequency input associated with a human body acting as anantenna.

At step 904, the strength of an input signal is determined. For example,resonance detector 304 determines the strength of an electric current,pressure sensor 404 may determine the amount of pressure that is appliedto casing 402, photodetector 506 may determine the amount of light thatis reflected through casing 502, frequency detection module 604determines the strength of the frequency input and RF circuit 706 maydetermine the strength of a radio frequency input.

At step 906, a determination is made as to whether the input signalmeets a predefined threshold. If the input signal meets a predefinedthreshold, method 900 proceeds to step 908, otherwise to step 910.

At step 908, a tag mode on NFC device is enabled. For example,controller 202 receives a signal to activate the tag mode on NFC device200, as described herein.

At step 910, an NFC device is disabled. For example, controller 202receives a signal to disable the tag mode on NFC device 200.

CONCLUSION

It is to be appreciated that the Detailed Description section, and notthe Abstract section, is intended to be used to interpret the claims.The Abstract section may set forth one or more, but not all exemplaryembodiments, of the invention, and thus, are not intended to limit theinvention and the appended claims in any way.

The invention has been described above with the aid of functionalbuilding blocks illustrating the implementation of specified functionsand relationships thereof. The boundaries of these functional buildingblocks have been arbitrarily defined herein for the convenience of thedescription. Alternate boundaries may be defined so long as thespecified functions and relationships thereof are appropriatelyperformed.

It will be apparent to those skilled in the relevant art(s) that variouschanges in form and detail can be made therein without departing fromthe spirit and scope of the invention. Thus the invention should not belimited by any of the above-described exemplary embodiments, but shouldbe defined only in accordance with the following claims and theirequivalents.

1. A system for activating an NEC device, comprising: a sensor module,configured to receive an input signal, wherein the input signal isgenerated by a contact with an electronic device; a measuring module,configured to: measure the strength of the input signal; determinewhether the input signal meets a predefined threshold; and activate theNFC device included within the electronic device when the input signalmeets a predefined threshold.
 2. The system of claim 1, wherein themeasuring module is further configured to activate a tag mode on the NFCdevice.
 3. The system of claim 1, wherein the measuring module isfurther configured to deactivate the NFC device when the input signaldoes not meet the predefined threshold.
 4. The system of claim 3,wherein the measuring module is further configured to de-activate a tagmode on the NFC device.
 5. The system of claim 1, further comprising: aplurality of casings, wherein each casing includes the sensor module. 6.The system of claim 1, wherein the sensor module is a resonance devicethat includes an oscillating circuit and the measuring module includes afrequency detection module.
 7. The system of claim 6, wherein theresonance device includes a conductive ink.
 8. The system of claim 6,wherein the resonance device includes a printed circuit board (PCB). 9.The system of claim 1, wherein the sensor module is a pressure sensorand the measuring module is a resistance measuring module.
 10. Thesystem of claim 1, further comprising a light source configured to emitlight and the measuring module is a photodetector.
 11. The system ofclaim 1, wherein the measuring module is the frequency detection modulethat measures the change in the frequency emitted by an antenna module.12. The system of claim 1, wherein the sensor module includes aconductive surface and wherein the measuring module is an RF circuit.13. A computer-implemented method for activating an NFC devicecomprising: sensing an input signal, wherein the input signal isgenerated by a contact with the NFC device; measuring the strength ofthe input signal; determining whether the strength of the input signalmeets a predefined threshold; and activating the NFC device that isincluded within an electronic device when the input signal meets thepredefined threshold.
 14. The method of claim 13, farther comprisingsensing a plurality of input signals from a plurality of casingsattached to the electronic device.
 15. The method of claim 13, whereinthe activating further comprises activating a tag mode on the NFCdevice.
 16. The method of claim 13, further comprising: deactivating theNFC device when the input signal does not meet the predefined threshold.17. The method of claim 16, wherein the deactivating further comprisesdeactivating a tag mode on the NFC device.
 18. The method of claim 13,wherein the measuring further comprises measuring a change in frequency.19. The method of claim 13, wherein the sensing further comprisessensing a change in a tuning element.
 20. The method of claim 13,wherein the measuring further comprises measuring resistance of anelectric circuit.
 21. The method of claim 13, wherein the sensingfarther comprises sensing pressure on a casing of the electronic device.22. The method of claim 13, wherein the sensing further comprisessensing a light reflected from a light source.
 23. The method of claim13, wherein the measuring further comprises measuring the rate ofreflection of a light reflected from a light source.
 24. An article ofmanufacture including a computer-readable medium having instructionsretrieved thereon that, when executed by a computing device, cause thecomputing device to perform operations for activating an NFC devicecomprising: sensing an input signal, wherein the input signal isgenerated by a contact with the NFC device; measuring the strength ofthe input signal; determining whether the strength of the input signalmeets a predefined threshold; and activating the NFC device that isincluded within an electronic device when the input signal meets thepredefined threshold.
 25. A system for activating an NFC device,comprising: a plurality of sensor modules that include a conductivematerial on a plurality of casings on an electronic device, wherein eachsensor module is configured to receive an input signal, the input signalis generated by contact with conductive material on each casing; aninsulating material that surrounds each sensor module; a measuringmodule, configured to: measure the strength of the input signal;determine whether the input signal meets a predefined threshold; andactivate the NFC device included within the electronic device when theinput signal meets a predefined threshold when contact with theelectronic device occurs.
 26. The system of claim 25, wherein at leasttwo of the sensor modules are in parallel and the sensor module sensesshorting when contact occurs with the electronic device on each casingthat includes the respective sensor module.
 27. The system of claim 25,wherein the measuring module is an ohmmeter.